bustion and aftertreatment operation. Research efforts are now being guided through fundamental analyses based on laboratory measurements supplemented with advanced simulation.

  • The establishment of the working group Crosscut Lean Exhaust Emissions Reduction Simulation (CLEERS), whose membership of industry, academic, and government researchers collaborates to guide research activities.

  • Demonstrated peak thermal efficiency of laboratory engines operating at speeds and loads corresponding to peak efficiency has increased about 2 percentage points to over 41 percent. This represents an increase of about 10 percentage points compared to current OEM engines.

  • Experimental demonstration of Bin 5 emissions using a NOx adsorber and a urea selective catalytic reduction (SCR) system.

The technical barriers for the advanced combustion and emissions control technologies are those of implementation, development, and cost. Specifically,

  • Implementation and control of advanced combustion approaches into the operating regime of the engine, which includes combustion mode switching and transients.

  • Developing the aftertreatment systems that will effectively couple with exhaust gas characteristics of advanced combustion approaches and fuel changes.

  • Reducing the cost of aftertreatment systems.

Fuel Cells

There is ample evidence of steady progress in most key fuel-cell-related technical areas, providing steady movement toward both performance and cost goals. There have been no breakthrough achievements, with the possible exception of a novel approach to the design and fabrication of the fuel cell membrane electrode assembly (MEA). The design, reported by 3M, eliminates the corrosion-prone carbon support structure and utilizes nanoscale metallic whiskers and a vacuum-deposited, thin film of catalyst. This approach, while not yet proven, offers the potential for simultaneously increasing fuel cell durability and reducing costs. The cost reductions would come from both a reduction in platinum loading and a configuration much more compatible with mass manufacturing. The performance increase would come primarily from better utilization of the catalyst.

Some other notable fuel cell achievements are these:

  • The development of a reinforced membrane that improves durability with no apparent loss in performance;

  • A better understanding of catalysts, especially platinum alloys, which



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